Welcome to the forum Jake. Although we can't comment on the TH, we are among the 'cheerleaders' who own the Grand Design product. When we were shopping, the Reflection was the only thing I found that fit the weight and length limits and had a floorplan that worked. Access to the fridge was critical for us. I too was concerned about a brand new company. Since we definitely wanted to change the 15" tires to 16" LT tires, I sent an email question via the Grand Design website. I had a response the next day from the Reflection product manager that the tires would fit. We traveled to see a unit, and measured, and the tires wouldn't fit. I sent another email to Grand Design, and within 3 days they had their supplier make the change so the tires fit on all models, and offered to work with our dealer to ensure we had the change. Between that and comments folks had made after taking the factory tour, my concerns lessened. So far we have spent about 115 nights and been nearly 7000 miles in our Reflection, and are very happy with our choice.
Like any brand, there are some issues and things that need fixing. It would be nice if everything were perfect, but things just don't work that way. That said, Grand Design customer support has been outstanding. We are fortunate to have a good dealer, but many of the issues I have read about on the forum can be attributed to the dealer not doing any PDI and not stepping up for warranty work. I've also seen many cases on the forum where one of the Grand Design company owners has gone to bat by calling the dealer to get things worked out. Watching the changes in the different models, it is obvious that feedback the company is getting is showing up in little changes in the designs.
Customer support is outstanding. I am amazed at all the posts that talk about 'Grand Design fixed this for us, even though we were out of warranty'. Jerry and his team seem to go the extra mile. We thought we had an electrical problem (turned out it was the campground), and got an email from customer support to call them -- we talked it through on the phone. Janice helps lots of us via this forum.
We attended the inaugural rally in Elkhart this September. The rally was organized by owners like us (thank you Dave and Steve for all your work), and was supported by Grand Design. The factory tour was impressive. Meeting the company owners again reinforced what others have said above. After listening to and speaking with them, I almost felt that I wanted to go to work for them (however, loving retirement won out on that one)!
Best of luck in your research. I'm sure you will get some input on the toyhauler portion of this forum. You'll also get insight by looking at the Tech Support section of the forum.